High silicon, aluminum alloys of various compositions are normally used in permanent mold or die casting applications, although some are also used for sand casting. Silicon contents may vary from 2.0% to 22.0% in the various alloys cast into dies, but normally these alloys contain between 5.0% and 12.0% silicon. The aluminum alloys of the new invention, therefore, would in their broadest conception, include the following elements in the ranges indicated:
______________________________________ Si Cu Mg Zn Fe Mn Ni Ti Cr Others ______________________________________ 5.0 .50 1.5 2.0 1.35 .65 .50 .20 .15 .15 22.0 7.00 5.5 8.0 max. max. max. max. max. max. ______________________________________
For economic and other considerations such as casting quality, aging characteristics, hardness, growth, high temperature strength, etc., the following narrower ranges of composition would more aptly describe the alloys of the new invention:
______________________________________ Si Cu Mg Zn Fe Mn Ni Ti Cr Others ______________________________________ 7.0 2.0 2.0 3.5 1.20 .50 .35 .15 .10 .10 12.0 4.0 4.0 6.5 max. max. max. max. max. max. ______________________________________